Counterbore



Aug. 21, 1923. I 1,465,612

w. s. MORSE COUNTERBORE Filed Sent. 50, 1921 31mm William /0 r336 Patented Aug. 21, 1923.

WILLIAM S. MORSE, 0F DETROIT, MICHIGAN.

oounrnmionn Application filed September 30, 1921. Serial No. 504,527.

specification, reference being had therein to the accompanying drawings.

The invention relates to counterbores and has for its object the provision of a simple and effective means whereby the cutter may be readily connected to and firmly held in its holder without liability of the cutter working or pullin out of the holder or. turning therein. ith this and other objects in view, the invention resides in the novel features of construction as more fully hereinafter set forth, I

In the drawings:

Figure 1 is a side elevation of a counterbore embodying my invention;

Figure 2 is a cross section on the line 2-2of Figure 1; p

Figure 3 is a side elevation of the cutter unit.

1 is the cutter having a shank with the cylindrical portion 2 and the polygonal portron 3, the cylindrical portion having a diameter such that its face extends beyond the faces of the polygonal portion, which latter is located upon the inner end of the shank. This shank is adapted to engage in the socket of the holder 4 having the cylindrical and poly nal bearing portions 5 and 6 respectively or engagement with the" cylindrical and polygonal portions respectively of the cutter shank. With this arrangement, the cutter 1 is driven from the holder 4 by the polygonal bearing portion 6 of the holder in engagement with the polygonal portion 3 of the cutter shank.

For detachably holding the cutter in firm engagement with the socket, there is the re silient split ring 7 of round cross section located in the annular groove 8 of the cylindrical portion 5, this resilient split ring being normally contracted to extend slightly inward beyond the face of the cylindrical hearing portion. 9 is an annular groove in the cylindrical portion 2 of thecutter' shank adapted for engagement in by the resilient split ring when the cutter with its shank are in place. The resilient split ring has a snap engagement with the cylindrical portion ofthe cutter shank so that it will firmly hold the cutter shank in the holder socket with-' out liability in out.

o disengage the cutter from the holder, the latter is provided with diametrically 0pp-osite radial slots 10 in its outer end adapted for engagement by a suitabletool such as a screw driver which may be inserted under the inner end of the cutter to pry the latter away from the holder and to disengage the resilient split ring from the annular groove in the cylindrical portion of the cutter shank. 11 is a pilot which is secured to the cutter 1 by means of the split nut 12 threadedly of the former working or pullengaging the inner end of the pilot stem 13 and having the conical end 14 adapted to seat in a conical recess in the inner end of the cutter shank.

From the above description it will be readily seen that I have provided a simple and effective means for securin a cutter to a holder which will permit 0 ready attachment of the cutter by tapping the latter inwardly to spring the resilient split ring over the cylindrical portion of the cutter stem and into engagement with its annular groove. Moreover, the cutter may be readily removed by inserting a screw driver or the like into one of the radial end slots of the holder and ing the cutter away from the holder until tlie resilient split ring has become disengaged from the annular groove in the cutter shank. Y i

What I claim as my invention is:

1. The combination of a tool holder having a socket provided with a cylindrical bearing portion at its outer end and a lygonal portion located inwardly from said cylindrical bearing portion, a tool having a shank provided with a cylindrical portion machined to close fit with the cylindrical bearing portion of said holder and also provided with a polygonal portion engaging the polygonal bearing portion of said holder,

said polygonal portion being centered on 2. The combination of a tool holder having a socket provided with co-axial cylindrical and polygonal bearing portions centered on the axis of the] holder, the faces of said polygonal bearing portion being symmetrically arranged with respect to the axis of said holder, a tool having a shank provided with a lindrical portion machined to close fit with the cylindrical beara ing portion of said holder and also provided with a co-axial polygonal portion engagin the polygonal bearing portion of said holder, said polygonal portion being centered on the axis of said tool and having its faces symmetrically distributed with respect to the axis of said tool, and resilient holding means detachably engageable withthe cylindrical portion of said tool and arranged wholly g Within the periphery of said holder.

ature.

In testimony whereof I affix s 

